A prior art technique disclosed in Tokkai Sho61-105228 published by the Japan Patent Office in 1986 reduces engine torque when the shift lever position is shifted from a stationary range position to a running range position in a stationary state of the vehicle. The prior art technique delays the ignition timing of the engine in response to the engagement of a forward/reverse clutch used for starting the vehicle. Consequently torque inputted to the clutch from the engine is reduced in the time period from the commencement of engagement of the forward/reverse clutch to completion of engagement. Thus, output torque from an automatic/transmission is reduced in this time period. In this manner, it is possible to suppress differences in output torque of an automatic/transmission (torque differentials) before and after the shift of the automatic transmission from a stationary range to a running range. Furthermore it is possible to suppress torque shock associated with clutch engagement.